Been working on this for a while but am waiting on some parts so thought this may be of interest to some.

Design brief for this was a lightweight mid-drive that could handle some power while still holding some resemblance of a bicycle. In short the head tube angle is 69% which seems to handle Ok and the frame is 105mm wide which is still enough for lipo's or 18650 (5 cells wide fits) but bike like. Frame is designed to handle either a big block or Revolt 160 short coupled with an Adappto Max E but am still waiting for the Revolt to turn up (Israel Post is slow beyond words). Frame is constructed of 1.2mm Cro molly which is somewhat hard to source in Australia for a decent price but it is light and strong which is what I was after. In order to minimise weight I have gone with a stressed motor case which takes the majority of engine and suspension loads (can't beat circles for strength) and I have tried my best to have the frame look like a bike and not a metal box with wheels.

With the exception of a few pieces I had laser cut the entire frame was cut on my homemade plasma cutter and was made with some basic workshop tools and TIG welder. For those expert welders out there I am self taught and still learning so it may not be the prettiest but they appear strong enough.

Slowly coming together. Had to do some machining for the rear hub spacers, bearing support, sprocket and brake. Still working on the freewheel attachment as I stuffed up the threading process (left hand thread is real fun for someone who hasn't done any matching since high school). Very happy with the chain line for the motor side but the peddle side is going to need some minor work but nothing too bad. The inclusion of peddles has proven the most difficult part of this build to ensure the chain is lined up and goes around the swing-arm etc.

Hard to see in this image but the motor chain fits inside the crank arm and goes above the bottom bracket. To start with I will be running a 60 tooth rear sprocket (in image) and a 12 or 13 teeth drive sprocket and see how the revolt performs.

The rear shock has a 400 pound spring at the moment and it is way too soft and drops a fair bit when I put my weight on it. I have ordered a 550 lb spring to firm it up but I fear I may have to move the rear shock down and further back to reduce the leverage on the shock. That is going to be a minor PITA if I have to move it but if this is the only issue I end up with I will be happy. On a positive note, the swing arm and frame has turned out very stiff with no bending or side to side movement which is something I was worried about.

Laced up the rear wheel with 12G spokes and 19*1.4 motorbike rim and trial tyre and it came together nicely (thanks glowworm cycles who got me the spokes the next day).

Yes, this is totally awesome 9lives. Have fun with the remainder, I can't wait to see completion with the drive and power specifics. Parallel drive is one challenge, besides that nice looking cromoly frame!

What power are you shooting for? I have no idea what kind of freewheel to match with an rv160!!

It will fit 20s2p lipo with internal adaptto max-e controller or at least 18s10p 18650's with external controller. I'll start with lipo to keep with the lightweight bike look but if the revolt delivers decent power will switch over to 18650 pack.

Rodney, the Phaser with upgraded mxus is pushing 11kw so if I get anywhere near its performance I will be over the moon with this. Not a lot of real world performance data on 160 short so I am hoping it comes somewhere between the performance of a 4065 and hot mxus. The revolt only weighs 5kg so am a little sceptical of claimed 15kw peak but will see.

if you really want 10kW peak than a 10p pack 18650 will be quite stressed imho. you're talking 150A or 15A per cell.
even the lipo will need to be decent quality to not sag a lot. 2p means 75A for one pack or 20c. i would choose the best lipo cells you can find

izeman wrote:if you really want 10kW peak than a 10p pack 18650 will be quite stressed imho. you're talking 150A or 15A per cell.
even the lipo will need to be decent quality to not sag a lot. 2p means 75A for one pack or 20c. i would choose the best lipo cells you can find

Iceman, Good points but I have some Samsung 25r's set aside for build. 20 amp max cont per cell so 10p should be good for occasional 150 amp peak. Lifespan may be interesting though. Re lipos I run a min of 25c in the phasor but they are now the limiting factor. Pack is a few years old now and they won't go much beyond 11 kW when full.

Hi all, still plugging away with the frame now finished. In the spirit of 'red goes faster' it got a coat of flame red powder coat from a local shop. Very happy with the job noting they charged me $60 which I thought was very reasonable. All up the frame and swing arm with colour weigh 6.2kg which again I am very happy with assuming it doesn't break.

Image below shows a layer of 9s10P along with the foam block which represents the dimensions of an adaptto max-e. I stuffed up with the original shock mount location but fixing this has allowed the adaptto to go under the seat. All up can probably manage 20s10p but I only have enough 25R's for 18s10p so that will be it.

Almost done

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It's red alright...with black carbon fibre panels to hopefully offset. For those with keen eyes the metal bit on the swing arm is part of the chain tensioner.

Back from powder coat

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Next step is finally assembly and battery construction noting the Revolt is still yet to arrive. It's obviously taking a very slow boat but this has worked out positively as I have ended up doing things I might of missed if I was rushing to instal the motor.